JP 610422 64 discloses a linear motor having copper or aluminum fins for dissipating heat.
WO 97/40569 discloses a variety of rotary machine casings having cooling fins. FIG. 1 of WO 97/40569 shows a casing provided with splines parallel to the axis of rotation of the rotor, the machine having forced ventilation. FIG. 2 shows a casing provided with fins perpendicular to the axis of rotation, for providing cooling by natural convection.
Application EP 0 072 999 describes a rotary machine having fins extending parallel to its axis of rotation, inside a casing.
Other air-cooled electric machines are known from WO 90/13936.
FIG. 1 of the accompanying drawings is a diagrammatic perspective view of another known machine 1 comprising a stator 2 including a casing 3 made of cast iron with fins 7 extending parallel to the axis of rotation X of the rotor 4. The casing 3 is covered by a cover 5 serving to channel air between the fins 7. A fan 6 (with only the casing of the fan being visible) is fixed to the cover 5 of the machine, on top and at one end thereof, air being sucked in through the other end. In addition to the casing 3, the stator 2 also includes a magnetic circuit (not shown) made up of a stack of laminations having slots that receive stator windings.